* [tip: x86/iopl] x86/ioperm: Avoid bitmap allocation if no permissions are set
@ 2019-11-16 11:51 tip-bot2 for Thomas Gleixner
0 siblings, 0 replies; 2+ messages in thread
From: tip-bot2 for Thomas Gleixner @ 2019-11-16 11:51 UTC (permalink / raw)
To: linux-tip-commits
Cc: Thomas Gleixner, Ingo Molnar, Borislav Petkov, linux-kernel
The following commit has been merged into the x86/iopl branch of tip:
Commit-ID: 32f3bf67ee78332f2caec0984cb9d412cd0a3c23
Gitweb: https://git.kernel.org/tip/32f3bf67ee78332f2caec0984cb9d412cd0a3c23
Author: Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Tue, 12 Nov 2019 19:56:19 +01:00
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Sat, 16 Nov 2019 11:24:01 +01:00
x86/ioperm: Avoid bitmap allocation if no permissions are set
If ioperm() is invoked the first time and the @turn_on argument is 0, then
there is no point to allocate a bitmap just to clear permissions which are
not set.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
arch/x86/kernel/ioport.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/arch/x86/kernel/ioport.c b/arch/x86/kernel/ioport.c
index ca6aa1e..80fa36b 100644
--- a/arch/x86/kernel/ioport.c
+++ b/arch/x86/kernel/ioport.c
@@ -36,6 +36,9 @@ long ksys_ioperm(unsigned long from, unsigned long num, int turn_on)
*/
bitmap = t->io_bitmap_ptr;
if (!bitmap) {
+ /* No point to allocate a bitmap just to clear permissions */
+ if (!turn_on)
+ return 0;
bitmap = kmalloc(IO_BITMAP_BYTES, GFP_KERNEL);
if (!bitmap)
return -ENOMEM;
^ permalink raw reply related [flat|nested] 2+ messages in thread* [patch V3 07/20] x86/ioperm: Avoid bitmap allocation if no permissions are set
@ 2019-11-13 20:42 Thomas Gleixner
2019-11-15 21:12 ` [tip: x86/iopl] " tip-bot2 for Thomas Gleixner
0 siblings, 1 reply; 2+ messages in thread
From: Thomas Gleixner @ 2019-11-13 20:42 UTC (permalink / raw)
To: LKML
Cc: x86, Andy Lutomirski, Linus Torvalds, Stephen Hemminger,
Willy Tarreau, Juergen Gross, Sean Christopherson,
H. Peter Anvin
If ioperm() is invoked the first time and the @turn_on argument is 0, then
there is no point to allocate a bitmap just to clear permissions which are
not set.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
V3: Split out from large combo patch
---
arch/x86/kernel/ioport.c | 3 +++
1 file changed, 3 insertions(+)
--- a/arch/x86/kernel/ioport.c
+++ b/arch/x86/kernel/ioport.c
@@ -36,6 +36,9 @@ long ksys_ioperm(unsigned long from, uns
*/
bitmap = t->io_bitmap_ptr;
if (!bitmap) {
+ /* No point to allocate a bitmap just to clear permissions */
+ if (!turn_on)
+ return 0;
bitmap = kmalloc(IO_BITMAP_BYTES, GFP_KERNEL);
if (!bitmap)
return -ENOMEM;
^ permalink raw reply [flat|nested] 2+ messages in thread* [tip: x86/iopl] x86/ioperm: Avoid bitmap allocation if no permissions are set
2019-11-13 20:42 [patch V3 07/20] " Thomas Gleixner
@ 2019-11-15 21:12 ` tip-bot2 for Thomas Gleixner
0 siblings, 0 replies; 2+ messages in thread
From: tip-bot2 for Thomas Gleixner @ 2019-11-15 21:12 UTC (permalink / raw)
To: linux-tip-commits
Cc: Thomas Gleixner, Peter Zijlstra (Intel),
Ingo Molnar, Borislav Petkov, linux-kernel
The following commit has been merged into the x86/iopl branch of tip:
Commit-ID: 5487da6bf0775d996352442b89a8defbd671b4ae
Gitweb: https://git.kernel.org/tip/5487da6bf0775d996352442b89a8defbd671b4ae
Author: Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Wed, 13 Nov 2019 21:42:47 +01:00
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Thu, 14 Nov 2019 20:15:02 +01:00
x86/ioperm: Avoid bitmap allocation if no permissions are set
If ioperm() is invoked the first time and the @turn_on argument is 0, then
there is no point to allocate a bitmap just to clear permissions which are
not set.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191113210104.404509322@linutronix.de
---
arch/x86/kernel/ioport.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/arch/x86/kernel/ioport.c b/arch/x86/kernel/ioport.c
index ca6aa1e..80fa36b 100644
--- a/arch/x86/kernel/ioport.c
+++ b/arch/x86/kernel/ioport.c
@@ -36,6 +36,9 @@ long ksys_ioperm(unsigned long from, unsigned long num, int turn_on)
*/
bitmap = t->io_bitmap_ptr;
if (!bitmap) {
+ /* No point to allocate a bitmap just to clear permissions */
+ if (!turn_on)
+ return 0;
bitmap = kmalloc(IO_BITMAP_BYTES, GFP_KERNEL);
if (!bitmap)
return -ENOMEM;
^ permalink raw reply related [flat|nested] 2+ messages in thread
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2019-11-16 11:51 [tip: x86/iopl] x86/ioperm: Avoid bitmap allocation if no permissions are set tip-bot2 for Thomas Gleixner
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2019-11-13 20:42 [patch V3 07/20] " Thomas Gleixner
2019-11-15 21:12 ` [tip: x86/iopl] " tip-bot2 for Thomas Gleixner
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